World number two Roger Federer and American favourite Andy Roddick both cruise through in straight sets in their third-round matches at the Miami Masters.

Roddick survived a gruelling first set tiebreak against Russian Dmitry Tursunov, which he won 11-9, before going on to ease through the second set 6-2.

Federer enjoyed a routine 6-4 6-1 win over German Nicolas Kiefer but will face a surprise opponent in the fourth round after 15th-ranked Spaniard Tommy Robredo lost 7-5 6-3 to American qualifier Taylor Dent.

Dent's career looked finished in 2007 after he spent most of the year in a cast following a serious back injury, but has come back impressively.

Nadal rode his usual powerful forehands to the lopsided win over Murray, hitting 10 winners from that side to Murray’s one. Nadal also was efficient at the net, winning eight of 11 points to Murray’s 5-of-10.

With the swirling wind making the service toss difficult, neither player served an ace.

INDIAN WELLS, California (AFP) - Scotland's Andy Murray defeated world number two Roger Federer 6-3, 4-6, 6-1 here Saturday to reach the final of the Indian Wells ATP Masters series tournament.

Murray, the world number four, has now won six of his eight career meetings against the mighty Swiss, including four in a row since losing to Federer in last September's US Open final.

Federer did little to help himself reverse that trend, with an uncharacteristic 32 unforced errors.

Federer was able to raise his game in the second set, but with Murray applying pressure from all over the court he couldn't find an answer in the third.

"Way too many errors," said Federer, who was playing his first tournament since falling to world number one Rafael Nadal in the Australian Open final.

The 27-year-old, who will become a father in the summer, spent the intervening six weeks recovering from a lingering back injury.

In the final, Murray will face either Nadal or seventh-seeded American Andy Roddick.

Murray is bidding for his third title of the season, despite being slowed by an ankle injury and a virus.

The 21-year-old Briton had a worrying moment in the third set when he appeared to twist an ankle and fell to the ground with a cry of pain on the second point of the fourth game - but he still managed to break Federer for a 3-1 lead.

He broke again to lead 5-1, and in the next game saved two break points before sealing the win on his fourth match point with a 130 mile per hour service winner that Federer could only smack out of court.

"He's a great counterpuncher," Federer said of what made the young Scot such a tough opponent.

"He reads the game really well. He's got great feel. He knows he doesn't have to play close to the lines because he knows he can cover the court really well. I think that calms him down mentally."

Federer's greatest chance came early, when he took a 0-40 lead on Murray's serve in the fourth game of the opening set. But five straight wayward backhands cost him the game.

"I would have loved to go in front with the lead," Federer said. "We had a tough rally as well at 30-40. Who knows if I maybe win that point, maybe he can't play the way he played all match long."

Federer added that he could only turn his attention to the Masters series tournament starting in Miami next week.